/Engine/Source/Runtime/Core/Public/Templates/SharedPointer.h
Special constructor used internally to statically cast one weak pointer type to another. You should never call this constructor directly. Instead, use the StaticCastWeakPtr() function. This constructor creates a weak pointer as a weak reference to an existing weak pointer after statically casting that pointer's object. This constructor is needed for static casts.
template<typename OtherType> TWeakPtr ( [TWeakPtr](API\Runtime\Core\Templates\TWeakPtr)< OtherType, Mode > const & InWeakPtr, [SharedPointerInternals::FStaticCastTag](API\Runtime\Core\Templates\FStaticCastTag) )